One of the important problems central to androgen action is the role of the nuclear acceptors, the chromosomal molecules to which androgen-receptor binds, commonly demonstrated in dilute salt extract of target cell nuclei. It is proposed to isolate the soluble acceptor from 0.35 M NaCl extract of rat prostate chromatin, to purify the acceptor by affinity and ion-exchange chromatography, and to study its possible effect on transcription. Additionally, the 2 M NaCl-insoluble chromatin (residual) fraction from rat prostate also target-specifically interacts with the androgen-receptor complex. This suggests the presence of a second acceptor. Efforts will be made to solubilize the residual fraction and to examine the ability of the solubilized residual proteins to interact with androgen-receptor complex under various conditions. If successful, it will be attempted to partially purify and characterize the solubilized residual acceptor.